The Matricellular Protein SPARC Decreases in the Lacrimal Gland At Adulthood and During Inflammation.

Purpose: Secreted protein acidic and rich in cysteine (SPARC) is a matricellular glycoprotein abundantly expressed in basement membranes and capsules surrounding a variety of organs and tissues. It mediates extracellular matrix organization and has been implicated in cell contraction. Here, we evaluated the expression of SPARC in the murine lacrimal gland at adulthood and during inflammation. Methods: Lacrimal glands of young mice (4-6 weeks old) and adult mice (32-40 weeks old) were used for extraction of DNA, RNA, and protein. The presence of SPARC was assessed by quantitative PCR, ELISA, and immunofluorescence microscopy. 5-Methylcytosine and DNA methylation were evaluated using ELISA and bisulfite genomic sequencing, respectively. The effects of cytokines and inflammation in Sparc expression were evaluated in vitro and in the non-obese diabetic (NOD) mouse model of Sjögren's syndrome. Results: The mRNA and protein levels of SPARC were downregulated in lacrimal glands of mature adult mice presenting age-related histological alterations such as increased deposition of lipofuscin and lipids. Epigenetic analyses indicated that glands in adult mice contain higher levels of global DNA methylation and show increased hypermethylation of specific CpG sites within the Sparc gene promoter. Analysis of smooth muscle actin (SMA)-green fluorescent protein (GFP) transgenic mice revealed that SPARC localizes primarily to myoepithelial cells within the gland. Treatment of myoepithelial cells with IL-1ß or TNF-α and the development of inflammation in the NOD mice led to decreased transcription of Sparc. Conclusions: SPARC is a novel matricellular glycoprotein expressed by myoepithelial cells in the lacrimal gland. Loss of SPARC during adulthood and chronic inflammation might have detrimental consequences on myoepithelial cell contraction and the secretion of tear fluid.

Anti-inflammatory effects of an autologous gold-based serum therapy in osteoarthritis patients.

Osteoarthritis (OA) involves activation and recruitment of immune cells to affected joints, including the production of pro-inflammatory cytokines. Here, a gold-based autologous serum therapy is investigated for its effect on peripheral blood cell composition and cytokine levels in OA patients. From six OA patients serum and blood samples were collected before and after second therapy treatment for analysis of peripheral blood cell composition as well as cytokine levels compared to control samples. This therapy significantly downregulates CD4+ T cells and B cells in OA patients after second treatment compared to healthy controls. Monocytes are significantly upregulated in patients after second treatment Serum IL-9 and TNF-α levels are downregulated in patients after second treatment compared to healthy control serum. The activation status of immune cells was modulated after therapy in patients. Anti-inflammatory effects of the peripheral blood cell composition in OA patients can be seen after therapy treatment. After two treatments IL-9 and TNF-α are significantly downregulated in patient serum. Here, primary data of a new autologous therapy for OA treatment and its modulatory effects on cytokines are presented.

Production and Secretion of Gelsolin by Both Human Macrophage- and Fibroblast-like Synoviocytes and GSN Modulation in the Synovial Fluid of Patients with Various Forms of Arthritis.

Gelsolin (GSN) is an actin-binding protein involved in cell formation, metabolism and wound closure processes. Since this protein is known to play a role in arthritis, here we investigate how the synovial membrane with its specific synoviocytes contributes to the expression of GSN and how the amount of GSN expressed is modulated by different types of arthritis. Synovial membranes from adult healthy subjects and patients with rheumatoid arthritis (RA) and osteoarthritis (OA) are analyzed by immunofluorescence, Western blot and ELISA. Macrophage-like synoviocytes (MLS) and fibroblast-like synoviocytes (FLS) were isolated, cultured and analyzed for their potential to produce and secrete GSN. In addition, the GSN concentrations in the synovial fluid of various forms of arthritis are determined by ELISA. GSN is produced by the healthy and arthritic synovial membranes. Both forms of synoviocytes (MLS and FLS) release GSN. The results show that there is a significant reduction in GSN in the synovial fluid in adult patients with OA. This reduction is also detectable in adult patients with RA but is not as evident. In juvenile arthritis, there is a slight increase in GSN concentration in the synovial fluid. This study shows that primary MLS and FLS express GSN and that these cells, in addition to articular chondrocytes, contribute to GSN levels in synovial fluid. Furthermore, GSN concentrations are modulated in different types of arthritis. Further studies are needed to fully understand how GSN is involved in joint homeostasis.

Gold-based blood serum treatment promotes wound closure of corneal epithelial cell defects in primary in vitro experiments.

BACKGROUND: Wound healing disorders characterised by impaired or delayed reepithelialisation are a serious medical problem. In the present study, we show that gold-based blood serum therapy is a suitable therapeutic approach and shows a supportive effect in wound closure of human corneal epithelial cells (HCE) in primary in vitro experiments. METHODS: For this purpose, blood from healthy individuals was incubated without (S.Ctrl) or with gold-microparticles (S.Therapy) for 24 h. Prior to human epithelial cell stimulation (HCE), the gold particles were removed and the serum was diluted in DMEM (10 % or 30 %). Both groups of serum were compared after injury. HCE were cultured and injured (corneal in vitro wound model) and then stimulated with S.Ctrl or S. RESULTS: Treatment with serum from a gold-based serum therapy (S.Therapy) shows a supportive effect on wound healing in HCE cells in vitro. In addition, gold therapy supports the secretion of important cytokines normally associated with ocular surface wound healing (IL-1ß, IL-6, TNF-α and TGF-ß) in HCE cells. CONCLUSIONS: Therapy with gold-based blood serum significantly promotes the secretion and expression of cytokines and growth factors in HCE cells in vitro. Further preclinical experiments are necessary to demonstrate the influence of this therapy on HCE cells for possible clinical application on the human ocular surface and to prove its function also in poorly healing corneal lesions.

The distribution of conjunctival goblet cells in mice.

PURPOSE: To evaluate the density and distribution of conjunctival goblet cells in mice without clinical evidence of ocular surface diseases. METHODS: Immediately after euthanasia of C57BL/6 wild-type mice, the eyes including eyelids were removed and fixed in paraformaldehyde. Entire eyeballs and eyelids were cut in series along the sagittal axis from nasal to temporal on a microtome and then stained with Periodic Acid-Schiff acid to visualize the goblet cells. At each section stained in this way, the conjunctival goblet cells of the entire upper and lower lid conjunctiva were counted by light microscopy. Additional (transmission electron microscopy) (TEM)-Analysis on ultrathin sections was performed to evaluate morphological differences. RESULTS: The total number of conjunctival goblet cells differs markedly between individual animals. Categorisation into upper eyelid (UL) and lower eyelid (LL) and into regions (nasal, middle, temporal) revealed a significant increase of goblet cells from nasal to temporal in the UL and a significant decrease in the LL. CONCLUSION: The distribution of conjunctival goblet cells in mice differs considerably from humans and between individual animals. Therefore, precise selection of sampling and methods are needed to obtain comparable data. We recommend to use the middle region of the conjunctiva of UL/LL for goblet cell studies in mice. These findings are of particular interest for dry eye mouse models as well as pharmacological studies on mice with influence on their goblet cells.

Recombinant human gelsolin promotes the migration of human articular cartilage chondrocytes by regulating gene expression in vitro.

Objective: It is known that recombinant human gelsolin (rhuGSN) supports wound closure and migration processes in avascular tissue. Since articular cartilage degradation plays an important role in osteoarthritis (OA), we are investigating how rhuGSN affects regeneration processes in human articular cartilage and represents a promising new therapeutic approach for the treatment of OA. Methods: Primary human chondrocytes (phCs) from articular knee cartilage were cultured with different concentrations of rhuGSN to analyse its direct effect in vitro. In addition, phCs were stimulated with 10 ng/mL IL-1ß or TNF-α to simulate osteoarthritis in vitro and treated with different concentrations of rhuGSN to investigate the beneficial effect in disease treatment. Cytokine secretion and gene expression as well as wound assays were performed. Results: GSN significantly promotes wound closure in phCs after 60 h compared to untreated cells. After 24 h treatment with 30 µg/mL rhuGSN, TGF-ß secretion increases significantly in the in vitro osteoarthritis model. Gene expression of MMP1 as well as SPARC is reduced in chondrocytes due to treatment with GSN in the OA model. At the same time, CXCR4 expression increases significantly after 24 h treatment with 3 µg/mL GSN. Conclusion: In the in vitro model of osteoarthritis, rhuGSN promotes wound closure of chondrocytes by a supported migration as well as expression of reconstructive and down regulated expression of deconstructive genes concentration dependently. Further experiments are needed to fully understand the beneficial effect of gelsolin on human chondrocytes and to verify this promising approach for a pharmacological treatment of osteoarthritis.

Structure, regulation and related diseases of the actin-binding protein gelsolin.

Gelsolin (GSN), one of the most abundant actin-binding proteins, is involved in cell motility, shape and metabolism. As a member of the GSN superfamily, GSN is a highly structured protein in eukaryotic cells that can be regulated by calcium concentration, intracellular pH, temperature and phosphatidylinositol-4,5-bisphosphate. GSN plays an important role in cellular mechanisms as well as in different cellular interactions. Because of its participation in immunologic processes and its interaction with different cells of the immune system, GSN is a potential candidate for various therapeutic applications. In this review, we summarise the structure of GSN as well as its regulating and functional roles, focusing on distinct diseases such as Alzheimer's disease, rheumatoid arthritis and cancer. A short overview of GSN as a therapeutic target in today's medicine is also provided.